1. Field of the Invention
The present invention relates to a camera capable of carrying out various types of zooming control.
2. Description of the Related Art
It has conventionally been proposed to provide a camera having photographic modes designed for a number of specific photographic conditions, such as a portrait mode, a landscape mode and a close-up mode.
In a camera having such photographic modes, exposure is programmed so that various photographs which individually match the specific photographic conditions can be automatically produced, as by altering exposure conditions while taking account of the specific photographic conditions. However, it has not yet been proposed to automate the process of determining angles of view which individually match the specific photographic conditions, and there is the problem that a user occasionally fails to take a photograph which matches a specific photographic condition selected by the user.
A second problem to be solved by the present invention is described below.
Conventionally, there are known arts for automatically taking a fantastic or nonrealistic photograph while causing a focusing lens or a zooming lens to operate during an exposure cycle, or for creating a similar effect by performing multiple exposure while changing the position of focus.
However, it has not yet been proposed to provide a camera in which the process of effecting multiple exposure while changing the magnification of a subject to be photographed is automated so that it is possible to achieve a further photographic effect by utilizing such a known photographic art.
A third problem to be solved by the present invention is described below.
Conventionally, in the field of zoom lenses used for photography or other purposes, including zoom lens arrangements which are achieved in combination with cameras, it has been proposed to provide automated or electrically powered focusing or zooming for the purpose of enhancing operability or response speed during photography.
However, with a camera having such automated focusing or zooming, it is still difficult for a photographer to take a photograph which perfectly reflects an angle of view or a state of focus according to the photographic intention of the photographer. There are some cases where the photographer needs to manually perform focusing or zooming. As a result, if the photographer encounters a sudden shutter opportunity, he may miss the shutter opportunity because of a loss of time due to manual focusing or zooming. It is, therefore, desired to solve this problem. Incidentally, a proposal for automatically moving a focusing lens to a preset focus position (U.S. Pat. No. 4,783,676) and a proposal for automatically moving a zooming lens to a preset zoom position (U.S. Pat. No. 5,065,172) have been known.
A fourth problem to be solved by the present invention is described below.
Conventionally, photographic lenses for cameras have a depth-of-field scale, or the cameras have a reduced-aperture preview function for confirming a depth-of-field on a viewfinder screen.
However, in recent years, it has become common practice to omit such a depth-of-field scale or such a reduced-aperture preview function for the purpose of cost savings. Further, if a user of a camera having such a function is not a skilled photographer, it is difficult to fully utilize the function.